A widespread project database for Devonian–Carboniferous magmatism in the Sierras Pampeanas and Frontal Cordillera between 27° and 35°S (including petrological, geochemical, geochronological, and isotope data) is reviewed along with compiled data from the literature and some new results. Rather than the traditional tectonic interpretation of episodic subduction, microcontinent collision and orogenic collapse, we distinguish four main magmatic domains: 1) Devonian Arc, 2) Devonian Foreland, 3) Carboniferous Arc, and 4) Carboniferous Retro-Arc. Devonian segmented subduction led to two oceanic slab configurations: 1) flat-slab subduction in the outboard region and resubduction >800 km inland from the trench, including lithosphere delamination of the upper plate and break-off of the subducted oceanic slab, along with asthenospheric mantle upwelling (31°–33° 30′S), and 2) normal subduction (34° - 35°S). In the first configuration the arc magmatism was absent, but voluminous foreland magmatism was developed, including small-scale trondhjemites. In the second geodynamic setting arc magmatism with significant continental crust involvement was developed. During the latest Devonian and Carboniferous, arc and retro-arc magmatism occurred coetaneously between 27° and 31°S, with migration that could be explained by movement relative to hot asthenospheric mantle. The arc is represented by calc-alkaline granitoids, whereas retro-arc magmatism consisted of (a) metaluminous to weakly peraluminous A-type granites, and (b) strongly peraluminous A-type granites, these latter with sometimes incomplete isotopic homogenization of the parental magma. Devonian–Carboniferous magmatic evolution here is explained by segmented tectonic subduction and a switch-off and switch-on geodynamic model. Magmatic activity was mainly continuous from ca. 395 to 320 Ma, although compositional variations occurred through time and space (foreland, arc, and retro-arc). Major involvement of mantle sources in the genesis of the Carboniferous arc granites at 28°–30°S contrast with a dominant continental signature in the granites of the Devonian arc at 34°–35°S. These differences are explained by two different configurations in the subduction system related to advance (28°–30°S) or retreat (34°–35°S) of the subducted ocean slab. The main conclusion of this work is that the complex interaction of oceanic and continental plates can produce different types of magmatism (or its absence): subduction processes do not consist only of an oceanic plate sinking under a continental plate.

回顾了 27° 到 35°S 之间的潘佩亚纳斯山脉和前科迪勒拉山脉泥盆纪-石炭纪岩浆作用的广泛项目数据库（包括岩石学、地球化学、地质年代学和同位素数据）以及文献中的汇编数据和一些新结果。我们区分了四个主要的岩浆域：1）泥盆纪弧，2）泥盆纪前陆，3）石炭纪弧，和 4）石炭纪逆弧。泥盆纪分段俯冲导致两种大洋板块构造：1）外侧区域的平板俯冲和海沟内陆的再俯冲>800公里，包括上板块的岩石圈分层和俯冲大洋板块的断裂，随着软流圈地幔上涌（31°–33° 30'S），和 2）正常俯冲（34° - 35°S）。在第一种构造中，弧岩浆作用不存在，但发展了大量的前陆岩浆作用，包括小规模的长闪长岩。在第二个地球动力学背景下，具有显着大陆地壳参与的弧形岩浆活动得到了发展。在最新的泥盆纪和石炭纪，弧和弧后岩浆作用在 27°和 31°S 之间同时发生，迁移可以用相对于热软流圈地幔的运动来解释。弧以钙碱性花岗岩为代表，而弧后岩浆作用由 (a) 金属铝至弱过铝 A 型花岗岩和 (b) 强过铝 A 型花岗岩组成，后者有时具有不完全的母体同位素均质化岩浆。这里泥盆纪-石炭纪岩浆演化是通过分段构造俯冲和关闭和开启地球动力学模型来解释的。岩浆活动主要是从大约连续的。395 到 320 Ma，尽管随着时间和空间（前陆、弧形和后弧形）发生成分变化。地幔源在 28°–30°S 的石炭纪弧形花岗岩的成因中的主要参与与在 34°–35°S 的泥盆纪花岗岩中的主要大陆特征形成对比。这些差异可以通过与俯冲海洋板块的前进（28°-30°S）或后退（34°-35°S）相关的俯冲系统中的两种不同配置来解释。这项工作的主要结论是海洋和大陆板块的复杂相互作用可以产生不同类型的岩浆作用（或不存在）：